Baseline characteristics (N = 89)
| Characteristic . | No. of patients . | Reference value . | Cohort value . | |
|---|---|---|---|---|
| No. . | % . | |||
| Age at diagnosis, y | — | |||
| Median | 71.6 | |||
| Range | 42.9-91.0 | |||
| Age at onset of symptoms, y | — | |||
| Median | 64.6 | |||
| Range | 40.6-82.6 | |||
| Male sex | — | 35 | 39 | |
| Race | ||||
| White | — | 84 | 94 | |
| Black | — | 2 | 2 | |
| Native American | — | 1 | 1 | |
| Other | — | 1 | 1 | |
| Unknown | — | 1 | 1 | |
| Duration of follow-up, mo | — | |||
| Median | 66.5 | |||
| Range | 0.1-348.7 | |||
| Hemoglobin, g/dL | ||||
| Median | 85 | 10.2 | ||
| Range | 13.5-17.5 | 6.2-17.7 | ||
| Lactate dehydrogenase, μkat/L | ||||
| Median | 69 | 4.4 | ||
| Range | 2.0-3.7 | 2.0-16.5 | ||
| Bilirubin, μmol/L | ||||
| Median | ||||
| Range | ||||
| Total | 73 | 1.7-17.1 | 35.9 | 3.4-114.6 |
| Direct | 49 | 0-5.1 | 6.8 | 1.7-188.1 |
| Coombs testing, % positive | 71 | Negative | 67 | 94 |
| Monospecific anti-C3d, negative anti-IgG | 46 | Negative | 30 | 65 |
| Monospecific anti-C3d, positive anti-IgG | 46 | Negative | 13 | 28 |
| Monospecific anti-IgG, negative anti-C3d | 46 | Negative | 1 | 2 |
| Polyspecific, negative anti-C3d, negative anti-IgG | 46 | — | 2 | 4 |
| Monospecific anti-C3d, no other antibody testing performed | 3 | — | 3 | 100 |
| Polyspecific testing, no monospecific testing performed | 18 | — | 18 | 100 |
| Cold agglutinin titer*† | 79 | |||
| 1970-2007 | Negative | |||
| Median | 1:215-216 | |||
| Range | 1:22-1:221 | |||
| 2008-2012 | Negative | |||
| Median | >1:29 | |||
| Range | n = 19 | |||
| Characteristic . | No. of patients . | Reference value . | Cohort value . | |
|---|---|---|---|---|
| No. . | % . | |||
| Age at diagnosis, y | — | |||
| Median | 71.6 | |||
| Range | 42.9-91.0 | |||
| Age at onset of symptoms, y | — | |||
| Median | 64.6 | |||
| Range | 40.6-82.6 | |||
| Male sex | — | 35 | 39 | |
| Race | ||||
| White | — | 84 | 94 | |
| Black | — | 2 | 2 | |
| Native American | — | 1 | 1 | |
| Other | — | 1 | 1 | |
| Unknown | — | 1 | 1 | |
| Duration of follow-up, mo | — | |||
| Median | 66.5 | |||
| Range | 0.1-348.7 | |||
| Hemoglobin, g/dL | ||||
| Median | 85 | 10.2 | ||
| Range | 13.5-17.5 | 6.2-17.7 | ||
| Lactate dehydrogenase, μkat/L | ||||
| Median | 69 | 4.4 | ||
| Range | 2.0-3.7 | 2.0-16.5 | ||
| Bilirubin, μmol/L | ||||
| Median | ||||
| Range | ||||
| Total | 73 | 1.7-17.1 | 35.9 | 3.4-114.6 |
| Direct | 49 | 0-5.1 | 6.8 | 1.7-188.1 |
| Coombs testing, % positive | 71 | Negative | 67 | 94 |
| Monospecific anti-C3d, negative anti-IgG | 46 | Negative | 30 | 65 |
| Monospecific anti-C3d, positive anti-IgG | 46 | Negative | 13 | 28 |
| Monospecific anti-IgG, negative anti-C3d | 46 | Negative | 1 | 2 |
| Polyspecific, negative anti-C3d, negative anti-IgG | 46 | — | 2 | 4 |
| Monospecific anti-C3d, no other antibody testing performed | 3 | — | 3 | 100 |
| Polyspecific testing, no monospecific testing performed | 18 | — | 18 | 100 |
| Cold agglutinin titer*† | 79 | |||
| 1970-2007 | Negative | |||
| Median | 1:215-216 | |||
| Range | 1:22-1:221 | |||
| 2008-2012 | Negative | |||
| Median | >1:29 | |||
| Range | n = 19 | |||
Ten patients had records from outside laboratories indicating a positive cold agglutinin titer.
The method of reporting cold agglutinin titers changed in 2008; all results obtained after this date were reported as positive or negative for a titer greater than 1:29. Since 2008, all patients for whom cold agglutinin titers were measured had outcomes greater than 1:29.